There are two issues here. Your trees are just printed out wrong, they would actually work ... if it wasn't for another, more major problem with pickling which we were aware of for quite some time, but hoped it would not appear. I am not going into details, but it's about a certain inconsistency for which we hoped it wouldn't matter. The problem is that I see no other way of fixing it than redesigning a part of the kernel, which would take at least week of work. I hope I'd have time this week, but I can promise nothing.

I'm sorry, this is getting worse and worse the more I go into it. I'll have to put a note that pickling is unsafe - what you get at unpickling may or may not be the same this which you pickled.

We found out that Orange's structures are connected in such a way that they cannot always be unpickled, but we can make the problem rare and we can always detect whether the problem occurred and raise an exception in that case.

But it will require some work, and since I'm the only one who knows that part of Orange and since I'm going to vacation in a few days, it will have to wait. We will probably even postpone the problem and go after other, simpler and more commonly occurring bugs first.